Mosquitoes

Mosquitoes pose risks, and so do some of the chemicals used to fight them

Mosquitoes can carry serious diseases like West Nile virus. Currently, the risk of contracting West Nile in the Pacific Northwest is extremely low, but that’s not the case in some other parts of the country – or world. That risk could change at any time.

The pesticides in many repellents come with their own risks. Especially if used improperly, some of them may increase risks to people, wildlife and waterways.

The best defense is avoiding mosquitoes and covering up

Only the adult female mosquitoes suck blood. The rest eat flower nectar and help pollinate plants.

Take extra care during peak mosquito biting hours – from dusk to dawn.

Wear long sleeves and long pants.

Screen windows, and use mosquito netting over outdoor eating areas as well as baby strollers, cribs and hats.

Reduce mosquitoes without chemicals

Remove all standing water – in old tires, trays, cans, bottles, leaf-filled gutters, and crumpled up plastic. Mosquito larvae or “wrigglers” need still water only a fraction of an inch deep for several days to mature.

For pools or human-made ponds that don’t connect to natural water bodies, you can release mosquitofish to eat the larvae. Many county vector control agencies provide them for free. Never release them into the wild.

Mosquito-killing dunks that contain BTI or Bacillus thuringiensis israelensis are also safe to use.

Repellent candles may not be effective and they emit fumes that could trigger respiratory problems. Bug zappers may sound gratifying, but aren’t likely to help much.

Use repellents with care

Repellents are pesticides that come with some risks, so be sure to follow all label instructions. The most effective and relatively safe repellents contain one of the following active ingredients: DEET, Picaridin, oil of lemon eucalyptus, or IR3535. Other botanical repellents may be worth trying but their effectiveness varies and many contain allergens.

Use products in lotion, pump or towelette form, not aerosol sprays in pressurized containers that can get chemicals in your eyes, mouth or lungs. Repellents used to treat clothing are more toxic than most skin-applied products.

Choose a repellent concentration rated for the time span you’re outdoors, but not longer. Use products with the lowest effective concentration of repellent chemicals, particularly on children. Don’t use more than 30 percent DEET on anyone.

Sunscreen-repellent mixtures are more likely to cause overexposure to repellent.

Take extra precaution with kids

As with any pesticide, keep bottles of repellents out of reach of young children.

When using repellent on a child, apply it to your own hands and then rub them on your child. Avoid eyes and mouth and use sparingly around ears. Do not apply to children's hands because they often put their hands in their mouths.

Don’t use oil of lemon eucalyptus or its synthetic version “PMD” on children under 3 years old.

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